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  <title>Document</title>
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  <script>
    //1. split 把字符串 转换为 数组  和 join() 相反
      let str='pink$red$blue'
      console.log(str.split('$'));
      let str1='老王喜欢老绿喜欢老六'
      console.log(str1.split('喜欢'));
      let  str2='今天你做核酸了吗'
      console.log(str2.substring(4,6));
      let str3='今天疯狂星期四'
      console.log(str3.startsWith('疯狂'));
      let str4='雪糕老师在上课，饿死我们了'
      console.log(str4.includes('上课'));
  </script>
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